characters argument and plt.savefig

gyli / PyWaffle

🧇 Make Waffle Charts in Python.

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characters argument and plt.savefig #17

Open SG-phimeca opened 4 years ago

SG-phimeca commented 4 years ago

There seem to be a problem when saving figures as pdf with matplotlib.pyplot.savefig and using the characters argument in Waffle: some characters are replaced by others.

list_character = ["🖳", "🐍"]

from pywaffle import Waffle
from matplotlib import pyplot as plt

n_row = 4
n_column = 5

import numpy as np
list_value = np.ones(len(list_character))

fig = plt.figure(
    FigureClass=Waffle,
    rows=1,
    columns=len(list_character),
    values=list_value,
    characters=list_character,
    font_file="~/.fonts/Symbola.ttf",
    font_size=50
    )

plt.savefig("replaced_character.pdf")
plt.close("all")

yields the attached file (two snakes instead of a computer and a snake). The computer alone is correctly printed. Inverting the order yields two snakes.

replaced_character.pdf

gyli commented 4 years ago

Are you using the latest version, 0.4.1? I have tested the code above while I can't reproduce this issue.

SG-phimeca commented 4 years ago

Yes, I use 0.4.1. Maybe some other package should be updated?!

gyli commented 4 years ago

Since I can't reproduce the issue, it's kind of tricky to figure out what goes wrong with your result. But it would be great if we can answer the following questions:

Does it only happen to pdf files, or is it the same result when showing in a pop window or save with other image format?
Could you check fig._pa to make sure it is the right parameters being passed?
Could you please find a shareable notebook, such as Azure Notebooks, which can also produce the same result, so that I can take a look and maybe start debugging?

SG-phimeca commented 4 years ago

yes, it only happens when saving to pdf. Not in interactive mode, nor when saving to scg or png.
The value associated to 'characters' in fig._pa is correct.
It might take some time. I'll try.

gyli commented 4 years ago

Interesting. If so, I’m thinking if it’s not the code or package related, but more related to the font or pdf reader. Since you are using a custom font, which might not be included or supported by something.

SG-phimeca commented 4 years ago

Installing pycairo and adding matplotlib.use('cairo') before plotting the figure solved the problem.

gyli commented 4 years ago

Good to know that works for you! It does remind me that I have cairo installed on my mac while I didn't switch matplotlib's backend manually.